12 51 300 Removing and installing/replacing engine wiring harness section, ignition module cylinder 1-4 (N63 B40/44 O 1)

IMPORTANT: Read and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION) .

IMPORTANT: Screw back on all screw points of cable channels without fail! Some screw points are also ground points . If the wiring harnesses are not correctly screwed tight and secured, this may cause DME malfunction and failure!

Necessary preliminary tasks:

Read out the fault memory of the DME control unit.
Switch off ignition.
Remove right SUSPENSION CROSS-BRACE .
Remove right-hand INTAKE SILENCER HOUSING .
Remove right INTAKE DUCT .

Fig 1: Overview Of Engine Wiring Harness Section (Ignition Module Cylinder 1 To 4)
Courtesy of BMW OF NORTH AMERICA, INC.

Overview of engine wiring harness section, ignition module cylinder 1-4.

Unlock all connectors from ignition coils and injectors and detach.

Release screws (1).

Tightening torque 12 51 2AZ .

IMPORTANT: Screw back on all screw points of cable channels without fail. Some screw points are also ground points .

Fig 2: Identifying Screws

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If fitted:

Unscrew nuts (1).

Detach ground connections.

Fig 3: Identifying Ground Connections Nuts

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Release wiring harness if necessary from existing clips and clamps.

Feed out wiring harness and remove.

Installation note:

Check wiring harness installation arrangement.

Check plug connections for correct fit.

Check stored fault message.

Clear diagnostic fault entries from fault memory.